1. Field of Invention
The invention pertains, generally, to inserts that are placed in the pre-drilled holes of a bowling ball, and, more specifically to custom made inserts represented by a plurality of different sizes of the exact anatomical configuration of a finger or thumb of a specific bowler, which inserts can be easily interchanged one for the other, and which self-lock into the bowling ball hole of one or more bowling balls without necessity of adhesives.
2. Description of Related Art
It is a chronic problem for bowlers, and especially professional bowlers, that during the course of a game the size of a bowler's digits changes, causing the fingers or thumb to not fit properly in the respective bowling ball hole. Most commonly the digits swell over the course of a game, or several games. Sometimes, however the bowler's digits may shrink from their average size. For example, if upon beginning a game the room is somewhat cool, or the bowler is nervous, the digits may be somewhat reduced from their normal diameter, but over the course of usage, the fingers (and/or thumb) then increase in diameter. Throughout this document it will be noted that the word "finger" may be used in a general manner which is intended to include the thumb; i.e. as the equivalent of "digit".
As is well known to those versed in the state of the art, the solution to the problems of finger swelling and shrinkage and the proper fitting of fingers into both pre-drilled holes in bowling balls and inserts placed into those holes to aid the action of gripping the ball has been elusive. Resolution of the problem of finger size changes is the primary issue facing all makers of bowling ball finger inserts today because, in spite of the number of insert products available for improving the action of grip of a bowling ball, none of the known alternatives adequately address the problem of finger size changes.
There are a number of reasons for this lack of complete solution, including: that the swelling and shrinkage that take place are irregular and constantly changing, the swelling and shrinkage are temperature related, the digit size is related to the degree of use, the change in finger size is bi-directional, being both expansile and contractile, and the size changes take place in a rigidly confined area with a rigid non-anatomical perimeter represented by a circle or oval configuration; i.e., the interior side wall of the bowling ball finger or thumb hole. Further adding to the difficulty are the facts that the swelling is related to the specific body characteristics and the physiology of individual bowlers (e.g. some people retain more fluids in their systems and some people sweat more than others), and known inserts are firmly fixed (often permanently) into the ball by an adhesive or some sort of screw mechanism so that if there is a great size change in the bowler's digits a completely different ball with different sized inserts may be required.
Some patented attempts at a solution to the problem of bowler's finger swelling and shrinkage have been made and examples thereof are discussed below:
Todd and Hibler (U.S. Pat. No. 4,773,645) illustrate finger inserts glued into a bowling ball. The inserts are circular at the finger interface, having two different diameter sizes for the same insert individual piece, multiple "ribbings" to aid fixation. PA1 Bresin and Thielen (U.S. Pat. No. 5,330,392) also disclose finger inserts that are circular at their interfaces with the corresponding digits and control swelling through the use of multiple, external fluted grooves on the external surface of the insert, the inserts being glued in place in the bowling ball and thus not being interchangeable. PA1 Arutunian (U.S. Pat. No. 5,498,209) discloses a composite bowling ball insert as an attempt to automatically control finger swelling. The insert has two coaxially aligned cylinders with a circular shaped finger/insert interface and an air space separating the two cylinders. The Arutunian inserts are glued in place in the bowling ball holes. PA1 Seyler (U.S. Pat. No. 4,247,102) shows a circular finger interface cylinder screwed into the bottom of the bowling ball hole and fixed with a tapered wedge screw, the insert being removable by use of a spanner wrench tool. PA1 Aluotto (U.S. Pat. No. 4,968,033) discloses a construct of three concentric, nested, cup-like, circular receptacles, screw fixated into the bottom of the bowling ball hole.
The above examples of the known art all encompass structural features that are different from the present invention. Those features are best summarized as follows:
All of the above require a circular or oval shaped cavity within the insert to interface with the finger or thumb. This means that a human anatomical form must conform to a non-anatomical shape in order to fit into the insert. However, in reality, when the finger swells, it does not naturally expand uniformly as a circle or an oval because restraining ligaments force the finger shape to change non-uniformly and disproportionately, but always in the planar template (the normal general shape) of the normal, non-swollen individual finger of the individual bowler. This is definitely not a case of "one shape fits all", rather, with the previously described conventional inserts, one shape fits no one.
Accordingly, in order to address the above limitations in the art, the present invention is provided with an anatomically configured internal cavity that is custom shaped exactly to the precise anatomical form of each individual bowling finger of each individual bowler. Further, multiple sizes of this precise anatomical form (both larger and smaller) are presented that accept either expansion or contraction of the finger (which can be naturally expanded or contracted within the limitations of the natural anatomy, such as ligaments). Further, fixation of all known bowling ball finger hole inserts has conventionally been either by an adhesive or glue; or some variation of screw fixation to the bottom of the pre-drilled hole of the bowling ball, making the known inserts very difficult and often impossible to remove from a particular ball without destroying the insert. Thus, the known inserts cannot be said to be interchangeable or substitutable.
By contrast, the inserts of present invention do not require any adhesive, glue, or screw type mechanism to secure the inserts into a pre-drilled bowling ball hole. Rather fixation of the insert onto the hole is accomplished by using an interlocking projection, described below, fused to the external surface of the insert, at a point on the longitudinal axis of the insert where an insert diameter reduction begins. This interlocking projection extending from the external surface of the insert interfaces with a groove of the same size and shape within the inner wall of the pre-drilled hole of the bowling ball, thereby producing an automatic interlock and stabilizing-fixation of the insert inside the bowling ball hole.
Further still, known art has attempted to relieve swelling by a series of circumferential fluted grooves, inter-positional air space between insert walls, or multiple nested, concentric circular cylinders. The present invention employs none of these features. Because fluted grooves and interpositional air spaces as shown in the art do not address digital contraction, and because the nested cylinders are circular and non-anatomical in shape, (although sometimes capable of accommodating digital contraction) the present invention simultaneously addresses both the contraction and expansion of the bowler's fingers by using multiple size presentations of the exact anatomical shape of the non-swollen digit. The various presentations of the insert are made both larger than, and smaller than, the normal sized digit of an individual bowler, when the digit is neither swollen nor constricted, so that natural ligamentous constraints on the digital shape changes are addressed in both the expansile and contractile forms.
Also anatomical deformities of a particular bowler's fingers (such as calluses and bone growths) are easily and automatically incorporated into the new inserts. This is an important feature not found in non-anatomically shaped inserts of circular or oval form and provides a much greater degree of comfort for bowlers with such anatomical abnormalities.
The present invention also employs digital diameter reduction in a manner which is different than the patented of device of Todd and Hibler, which is designed for use of both ends of the described bowling ball insert for finger insertion. Further the device of Todd and Hibler is pressed uniformly at each end of the insert against the interior wall of the containment hole of the ball.
The present invention allows finger insertion only at the larger diameter outer end of the new insert, because of its anatomically correctly adapted shape. The diameter reduction begins at the interlocking projection and extends to the tip of the finger at the bottom end of the insert. The bottom end of the insert does not touch the bottom of the hole in the bowling ball, nor do the sides of the insert for the length of diameter reduction touch the inside wall of the rigid ball hole. Essentially, the portion of the present invention from the bottom end to the point just before the start of the interlocking projection along the length of the insert having diameter reduction is actually free-floating within the hole, enabling the compressible elastomer of which the insert is made to help in relieving some of the discomfort encountered during expansive digital swelling.
The present invention uses a circular plate with a central aperture incorporated into the bottom end of the insert just beyond the tip of the anatomically configured internal insert cavity. This plate enables facile, rapid manual removal of the insert from the ball hole and aids in the facile introduction of another i.d. size insert. An end-threaded rod mates with the centrally threaded portion of the plate allowing the insert to be simply lifted out of the ball hole. And further, the present invention can consist of multiple elastomeric components within a single insert, the different elastomers being employed for their specific properties of different hardness and softness, and different frictional characteristics. The combination of the multiple elastomeric components, as described hereafter, in a single "finger hole" insert aids the bowler in obtaining optimum performance, by effecting either a faster or slower finger (digit) extraction, as may be required, from the insert on release of the ball during bowling. Such construction and the effects thereof are found nowhere in the known art of inserts for bowling ball holes.
A further advantage of the bowling ball hole insert of the present invention is that it is extremely durable as compared to the art. With known inserts it is common for a competitive bowler to need to replace the inserts at least four times per year. By contrast, the new inserts, due to the described construction, will perform for at least a year, thereby making the new customized inserts very economical in the long run.